Where Did All the Insects on Car Windshields Go?

Have you noticed fewer bugs on your windscreen as you are driving? According to experts, there is a reason for this.

Car windshields used to be covered with dead instincts after a long drive, however in recent years there has been a noticeable decline. But what is the cause of this, could it be that the number of insects has decreased, or have windshield designs changes?

There have been a number of studies that aimed to find out if there is an actual decline in insect numbers that is resulting in fewer bugs on windscreens, or if it is something else.

According to Tomas Roslin, a professor of insect ecology at the Swedish University of Agricultural Sciences (SLU), the fact that car windshields have become less of an insect graveyard is due to both factors: new windshield designs, but also significant reductions in insect numbers.

A 2019 study in the UK conducted "splatometer" tests. Experts examined the number of bug splats in a small grid that was place over car registration plates, referring to this as a "splatometer". The study found 50% fewer impacts than a previous test in 2004.

There was another large-scale public experiment that involved 40,000 drivers attaching sticky films to their license plates. The findings were similar to that of the 2019 study in the UK, there was a considerable decrease in insect populations over time. 

It is also thought that the design of modern cars, including more aerodynamic shapes and smoother surfaces, likely contributes to fewer insects being splattered on windshields. However, the 2019 UK study also compared vintage cars with modern cars to see if their less aerodynamic shape had an impact, and found the opposite: modern cars hit slightly more insects. 

Studies confirm that insect populations are declining due to habitat loss from urbanization, deforestation, and agricultural expansion, increased pesticide use that kills beneficial insects and disrupts ecosystems, climate change altering life cycles and habitats, and pollution from heavy metals, plastics, and chemicals.

This decline is concerning because insects are vital for ecological balance and life on Earth. They pollinate plants, decompose organic matter, serve as food for many animals, and provide natural pest control, all of which support agricultural productivity and ecosystem health.